Validation of EN ISO method 15216 - Part 1 - Quantification of hepatitis A virus and norovirus in food matrices.

Hepatitis A virus (HAV) and norovirus are important agents of food-borne human viral illness, with common vehicles including bivalve molluscan shellfish, soft fruit and various vegetables. Outbreaks of viral illness due to contamination of the surfaces of foods, or food preparation surfaces by for example infected food handlers are also common. Virus analysis of food matrices can contribute towards risk management for these hazards and a two-part technical specification for determination of Hepatitis A virus and norovirus in food matrices (ISO/TS 15216:2013) was published jointly by the European Committee for Standardisation and the International Organization for Standardization in 2013. As part of the European Mandate No. M381 to validate 15 standards in the field of food microbiology, an international validation study involving 18 laboratories from 11 countries in Europe was conducted between 2012 and 2014. This study aimed to generate method characteristics including limit of detection, limit of quantification, repeatability and reproducibility for ISO 15216 - Part 1, the method for quantification, in seven food matrices. The organization and results of this study, including observations that led to improvements in the standard method are presented here. After its conclusion, the method characteristics generated were added to the revised international standard, ISO 15216-1:2017, published in March 2017.

A pan-European ring trial to validate an International Standard for detection of Vibrio cholerae, Vibrio parahaemolyticus and Vibrio vulnificus in seafoods.

Globally, vibrios represent an important and well-established group of bacterial foodborne pathogens. The European Commission (EC) mandated the Comite de European Normalisation (CEN) to undertake work to provide validation data for 15 methods in microbiology to support EC legislation. As part of this mandated work programme, merging of ISO/TS 21872-1:2007, which specifies a horizontal method for the detection of V. parahaemolyticus and V. cholerae, and ISO/TS 21872-2:2007, a similar horizontal method for the detection of potentially pathogenic vibrios other than V. cholerae and V. parahaemolyticus was proposed. Both parts of ISO/TS 21872 utilized classical culture-based isolation techniques coupled with biochemical confirmation steps. The work also considered simplification of the biochemical confirmation steps. In addition, because of advances in molecular based methods for identification of human pathogenic Vibrio spp. classical and real-time PCR options were also included within the scope of the validation. These considerations formed the basis of a multi-laboratory validation study with the aim of improving the precision of this ISO technical specification and providing a single ISO standard method to enable detection of these important foodborne Vibrio spp.. To achieve this aim, an international validation study involving 13 laboratories from 9 countries in Europe was conducted in 2013. The results of this validation have enabled integration of the two existing technical specifications targeting the detection of the major foodborne Vibrio spp., simplification of the suite of recommended biochemical identification tests and the introduction of molecular procedures that provide both species level identification and discrimination of putatively pathogenic strains of V. parahaemolyticus by the determination of the presence of theromostable direct and direct related haemolysins. The method performance characteristics generated in this have been included in revised international standard, ISO 21872:2017, published in July 2017.

An outbreak of acute pulmonary histoplasmosis in members of a trekking trip in Martinique, French West Indies.

BACKGROUND: Thirteen clustered cases of American histoplasmosis, a deep mycosis caused by Histoplasma capsulatum and acquired through inhalation of airborne spores was reported. Twenty-five persons traveled in Martinique, French West Indies. Thirteen underwent trekking and passed through a mountain tunnel full of bats (tunnel group). The 12 others performed canyoning and did not go through the tunnel (control group). Fifteen days after exposure, 1 patient of the tunnel group developed fever, chills, and cough. METHODS: The index case was diagnosed in the hospital, but 12 cases where initially diagnosed as prolonged influenza. All individuals were contacted and submitted to a phone questionnaire. They were asked about eventual occurrence of influenzalike symptoms, about activities practiced, and the notion of contact with bats. All were invited to have clinical examinations, chest x-ray films, and blood samplings. Serologic testing for histoplasmosis was performed by immunodiffusion. Clinical evidence of infection with H. capsulatum was obtained in all the remaining patients of the tunnel group and in none in the control group. Symptoms occurred with an acute onset in 11 to 23 days: fever and chills, severe asthenia, headaches, digestive tract involvement, and then cough, dyspnea, hepatic involvement. Pulmonary micro- or macronodules and mediastinal adenopathies were seen on radiograph and/or computed tomography scan. RESULTS: H. capsulatum serologic tests were positive in all 13 cases with presence of specific M and or H precipitins, 5 to 13 weeks after exposure, and were negative in control group. All patients were treated with itraconazole 200 mg per day during at least 2 months. Treatment was well tolerated; patients progressively recovered. Clinical and serologic follow-up was obtained for some patients at 1 and 4 years. The present study reports the first large outbreak of histoplasmosis acquired in Martinique. CONCLUSION: Histoplasmosis still occurs and is potentially serious. In patients returning from endemic areas, presenting prolonged influenzalike symptoms, clinicians should look for previous possible exposure to Histoplasma.